1. www.convergencetechnologycenter.org DUE 402356 Vincente D’Ingianni Director of Professional Services Binary Systems, Inc. vincente@binary-systems.com IMS Overview

2. www.convergencetechnologycenter.org 2 Contents  What is IMS?  Basic Principles  IMS building blocks  IMS Architecture  Why all the excitement?  Who needs IMS  Problems  Conclusions

3. www.convergencetechnologycenter.org 3 What is IMS? IMS is an architecture, it is not a protocol. Open-systems architecture that supports a range of IP-based services over both Private and Carrier networks, employing both wireless and fixed access technologies. IMS is defined by 3GPP.

4. www.convergencetechnologycenter.org 4 Basic Principles Access Independence Different Network Architectures Terminal and user mobility Extensive IP-based services

5. www.convergencetechnologycenter.org 5 IMS Building Blocks 1. An all-IP Core Network (CN) 2. An all-IP Radio Access network (RAN) 3. Multimedia call control based on SIP 4. Quality of Service (QoS) support for IP

6. www.convergencetechnologycenter.org 6 Management Provisioning Charging Number Mapping MGW SG/MGCF CSCF MRF HSS SIP, IP Control Layer AS SIP / OSA / CAMEL Application Layer IP/MPLSPSTN/PLMN GERAN, UTRAN, WLAN, xDSL,... Connectivity & Access Layer IMS Architecture

7. www.convergencetechnologycenter.org 7 6 HSS: Home Subscriber Server CSCF: Call Session Control Function: S-CSCF: Serving CSCF I-CSCF: Interrogating CSCF P-CSCF: Proxy CSCF BGCF: Breakout Gateway Control Function MGCF: Media Gateway Control Function AS: Application Server SCP: Service Control Point MGW: Media Gateway MRFC: Multimedia Resource Function Controller MRFP: Multimedia Resource Function Processor Applications and Services AS SCP Mobile UE GERAN UTRAN SGSN IM-SSF OSA-SCS CSCF HSS SGW Operator 1 CSCF BGCF Operator 2 BGCF MGCF MRFCMRFP GGSN Multimedia IP Networks CS Domain - or - PSTN - or - Legacy - or - External MGW SGW Alternative Access Network IMS Architecture

8. www.convergencetechnologycenter.org 8 Vertical vs. Horizontal Architecture Terminal Network logic Service 1 Service 2 Service 3 Replicated - not reusable Application logic Common functions Routing Terminal Network logic Replication of common functions Service 1 Service 2 Service 3 Routing Common functions

9. www.convergencetechnologycenter.org 9 Imagine starting a voice call on you home phone and transferring it seamlessly to your mobile as you drive to work. Imagine sending a multimedia message from your car that later appears on your TV screen. Imagine watching a movie on that same TV, pausing it in mid- show and then watching it on a wireless PDA as you relax in the garden. Imagine having a cell phone conversation with two or three friends and simultaneously sharing a video of the football match you are attending. Imagine that all of the above can be done with a single account, on a single log-in with multiple devices over any number of access networks These are only a few examples of seamless multimedia services that IMS will allow users to access “anywhere” at “anytime” Why all of the excitement?

10. www.convergencetechnologycenter.org 10 Who needs IMS? Fixed Network Users want Multimedia Conferencing Voice over IP Streaming Services Mobile Network Users want Push-to-X Location Based Services Mobile Gaming

11. www.convergencetechnologycenter.org 11 Who needs IMS? Network Providers want Fixed Mobile Convergence One service - one implementation for all access types New Business Models

12. www.convergencetechnologycenter.org 12 An everyday scenario Daniel Jacqueline In a taxi from the airport... Walking to the office... Mobile phone call Mobile phone Vincente Gerry

13. www.convergencetechnologycenter.org 13 An everyday scenario Daniel Jacqueline In a taxi from the airport... Walking to the office... Activates Video mode Views Images on his mobile Mobile phone Vincente Gerry

14. www.convergencetechnologycenter.org 14 An everyday scenario Vincente Daniel GerryJacqueline In a taxi from the airport...Walking to the office... Mobile phone Buddy list > select project work group Initiate PTT session In the office... Office PC Join PTT session Fixed line phone

15. www.convergencetechnologycenter.org 15 An everyday scenario Daniel Jacqueline At the hotel... Walking to the office... Laptop Computer Mobile phone Buddy list > personal list Invite others to Videoconference In the office... Office PCFixed line phone Join Videoconference Vincente Gerry

16. www.convergencetechnologycenter.org 16 An everyday scenario Daniel Jacqueline At the hotel... Walking to the office... Laptop Computer Mobile phone Participates in Videoconference In the office... Office PCFixed line phone Participates in Videoconference Opens presentation and shares it with his colleagues Vincente Gerry

17. www.convergencetechnologycenter.org 17 An everyday scenario Vincente Daniel GerryJacqueline At the hotel...Arrived in the office... Laptop Computer Office PC In the office... Office PCFixed line phone Switches from Mobile to PC Participates in Videoconference

18. www.convergencetechnologycenter.org 18 Problems and open issues Architecture complexity. Guarantees of QoS. IETF and 3GPP standardisation co-operation. SIP and IMS architecture are not mature enough to guarantee fully functioning network. Terminal complexity.

19. www.convergencetechnologycenter.org 19 There is still work to be done.... The current work in 3GPP is still unfinished and the discussion with IETF has just been started. The specification work still continue now.

20. www.convergencetechnologycenter.org 20 Selected Acronyms 3GThird Generation 3GPP(2)Third Generation Partnership Project (2) APIApplication Programming Interface ASApplication Server BGCFBreakout Gateway Control Function CAMEL Customised Applications for Mobile Enhanced Logic CSCFCall Session Control Function BICNBearer Independent Core Network GGSNGateway GPRS Support Node GPRSGeneral Packet Radio Service GSMGlobal System for Mobility IMSIP Multimedia Subsystem IPInternet Protocol IP-CANIP- Connectivity Access Network ISIMIMS Subscriber Identity Module IWFInter-Working Function LANLocal Area Network QoSQuality of Service RACSResource and Admission Control Subsystem RANRadio Access Network SCMSession Control Manager SGSNServing GPRS Support Node SIPSession Initiation Protocol SLAService Level Agreement UMTSUniversal Mobile Terrestrial Access